Objective: The objective of this study was to determine the prevalence and significance of perivascular soft tissue surrounding the hepatic artery on computed tomography (CT) after liver transplantation.
Materials and Methods: A total of 119 consecutive patients who underwent liver transplantation were retrospectively identified from a search of electronic medical records. Fourteen patients had histologic proof of posttransplant lymphoproliferative disease (PTLD). For each patient, the initial CT scan after transplantation, and the most recent CT scan if available, was analyzed for the presence of soft tissue in the porta hepatis region, particularly surrounding the transplanted hepatic artery. The hepatic artery was identified, and the maximum diameter of the soft tissue surrounding the vessel was measured and classified using the following scale: grade 0, none; grade 1, mild; grade 2, moderate; grade 3, moderate-large; and grade 4, large.
Results: Prevalence of perivascular soft tissue was 93% in the initial CT scans and follow-up studies. Comparing the initial and follow-up soft tissue measurements, 34% decreased, 62% were unchanged, and 4% increased. Using the Fisher exact test and a Mann-Whitney test, there was no statistically significant difference in the prevalence or diameter of perivascular soft tissue when comparing patients with pathologically proven PTLD and patients with no PTLD. Twenty-nine of the 119 patients underwent 68 positron emission tomography/CT scans in the time interval analyzed. Ninety percent of these patients had no abnormal fluorodeoxyglucose activity in the porta hepatis and portacaval regions.
Conclusions: The presence of isolated perivascular soft tissue in patients after liver transplantation is a common finding and is not associated with lymphoproliferative disease.